1. Field of the Invention
The present invention relates to a Braille-character display device capable of pressing a plurality of movable pins to represent Braille characters, and a portable terminal including the same.
2. Description of the Related Art
Recently, there have been commercially available portable terminals such as a mobile telephone, a PHS (Personal Handy-phone System), a PDA (Personal Digital Assistant) and a notebook-sized personal computer. The size and the weight of such portable terminals tends to be reduced. Through a portable terminal, a person with visual impairment can acquire various kinds of information from voice such as conversation and audio guidance.
In the portable terminal, however, acquisition of information from a conversation or audio guidance requires a sense of hearing. Consequently, a person with visual impairment and hearing impairment can not utilize the portable terminal. In addition, there is a bone conduction technique that allows a person to grasp voice via his/her jaw or cranial bone. However, this technique is adopted for acquisition of information from conversation or audio guidance, but can not be utilized for the purpose of reading data of a character string such as electronic mail and information on the Web.
In Braille, an aggregate of physically raised dots (a matrix size: 3×2 or 4×2) represents hiragana characters, and a person touches the aggregate with his/her finger to recognize the characters. For example, a person with visual impairment can acquire various kinds of information through such Braille characters.
Typically, Braille characters are written to a sheet of paper at prescribed spacings, and a user touches raised dots to recognize a word or a sentence. In Braille, however, representation of one hiragana character requires an area of about 25 square millimeters. Consequently, characters equivalent to one novel disadvantageously require a vast amount of paper media. Accordingly, such a paper medium is unsuitable in a case where a user carries a large amount of character data.
In order to avoid this disadvantage, the following technique is known: Braille-character display parts for displaying eight characters are provided radially on a surface of a disc, and Braille characters are updated successively by a mechanism that protrudes, holds or retreats pins corresponding to dots of the Braille characters. According to this technique, Braille characters are successively displayed by rotation of the disc, so that a Braille-character reading mechanism can be applied to a portable device.